\[ \large\mathcal{YiHsin}\;\mathcal{Sam}\;\mathcal{Lu} \]
\[ \Large D(a) = \cfrac{N}{N_{\text{doctors}}},\; a=\{\text{ Robot, LPS }\} \]
# Robot
nrow(Doc_Robot)/length(levels(Doc_Robot$手術醫師))
## [1] 8.214286
# LPS
nrow(Doc_LPS)/length(levels(Doc_LPS$手術醫師))
## [1] 8.528571
\[ \Large Med(a) = \cfrac{N_{\text{doctors}}(>median)}{N},\; a=\{\text{ Robot, LPS }\} \]
# Robot
nrow(R)/nrow(Doc_Robot)
## [1] 0.05652174
# LPS
nrow(L)/nrow(Doc_LPS)
## [1] 0.03936348